from tkinter import *

root=Tk()

Label(root,bg="red").place(relx=0.5,rely=0.5,relheight=0.75,relwidth=0.75,anchor=CENTER)
Label(root,bg="yellow").place(relx=0.5,rely=0.5,relheight=0.5,relwidth=0.5,anchor=CENTER)
Label(root,bg="green").place(relx=0.5,rely=0.5,relheight=0.25,relwidth=0.25,anchor=CENTER)


mainloop()
